Charles I. Jones is The STANCO 25 Professor of Economics at Stanford Graduate School of Business and a research associate of the National Bureau of Economic Research. Professor Jones has been honored as a member of the American Academy of Arts and Sciences, a fellow of the Econometric Society, and a co-editor of Econometrica. He is currently the area coordinator for the economics group at Stanford GSB. Dietrich Vollrath is professor of economics, and Chair of the department at the University of Houston. His research focuses on economic growth, and has appeared in the Review of Economic Studies, Journal of Economic Growth, Journal of Development Economics, and the American Economic Journal: Macroeconomics, among others. He is a past recipient of the Ross Lence Teaching Award.